For the general public making decisions on food choices is tough with the amount of information currently out there. What makes it worse is when the information conflicts.
During times like this often people look to those who have had success and just follow their example rather than get bogged down in the minutia of the science of the issues. Currently in the media age this is not helped by every few months a celebrity or fitness personality coming out with a new diet plan what displays the before and after pics and accompanying blurb from the person stating how fantastic the diet plan is.
So what’s a person to do in order to make good diet choices? Education is the best bet, cut through the sales pitch and get to the nitty gritty of each diet in order to make an informed choice. Below is a summary of the diets currently in favour. The marketing spiel along with the theoretical backing is presented before we dissect it and look at it from a real life perspective.
The Atkins/low carb diet
A high-protein, high-fat diet in which carbohydrates are severely restricted This diet has been around for a while but gained mainstream popularity when packaged as the Atkins diet. Essentially it revolves around reducing the carbohydrate consumption, depending upon which variant of the diet to anywhere between 30-150g of carbohydrates a day. The premise is that carbohydrates raise Insulin levels and this hormone shuts down fat usage as an energy substrate leading to easier weight gain. Typically most people see rapid weight loss when changing from a standard western diet to one of reduced carbohydrate. This primarily is due to glycogen losses which also hold water into a cell. As such initial losses of 3-6kg can be seen in the first few weeks.
Long term low carbohydrate diets haven’t been shown to hold that much more efficacy from lower fat, higher carbohydrate diets despite the improved weight loss in the initial stages. The benefit of this diet is that fat and protein which are still consumed have a good influence on satiety which makes sticking to a restricted calorie diet easier. Added to this physical affect of being less hungry, the restriction of not eating carbohydrates leads to a direct restriction of calories as individuals options in a free will environment is less. Look at most junk food and most will contain a significant amount of carbohydrates as well as sometimes fat – the elimination of carbohydrates makes dietary compliant choices quite small.
Considering this a low carbohydrate diet in the short term will make it easier both physically and psychologically to stick to. The negatives of this type of diet revolve around a few key points. Firstly, any diet which restricts food groups runs the risk of leading long term to either micronutrient deficiencies or issues surrounding dietary fibre intake and gut health long term. Secondly, any active individual will normally see a drop in performance within their sport or during training as Carbohydrates typically serves as the preferred energy use during high intensity activities.
The Paleo diet
A diet based on the types of foods presumed to have been eaten by early humans, consisting chiefly of meat, fish, vegetables, and fruit but excluding dairy or cereal products and processed food. Typically this means the following the recommendations as laid out by Robb Wolf, one of the proponents for the Paleo diet.
Foods to eat include fruits, vegetables, nuts, healthy fats, legumes, seafood.
Foods to avoid include processed foods, dairy, sugars, cereals, potatoes and alcohol
A diet which focuses on nutrient dense whole foods would seem to be a good option and despite the elimination of food groups they do offer greater dietary range than a low carbohydrate diet. Many fibrous food sources will easily be consumed in addition to vitamin rich foods such as fruit. Comparatively to a low carbohydrate diet, this type of diet will yield more opportunities in order to meet dietary needs and not become deficient any one nutrient.
Again this diet works well in eliminating many of the calorie dense modern foods which are often present in the diet of those who have become overweight. Whilst it offers more chance for calorie consumption the restriction towards foods higher in natural fats, fibre and protein will likely see a calorie deficit created long term if the diet is stuck to.
Again this type of diet often fails those who are active as the carbohydrate content is limited. In the Crossfit community where paleo styled eating has caught on the most you will find many of the top athletes will add in more starches from potatoes or rice in order to meet their energy needs and assist in recovery
Low fat diet
A diet containing restrictions in dietary fat with typically less than 15% of energy coming from fat. This has been the publics’ perception of diet for a long term as it ties in with government policy to reduce dietary fat in line with movements to improve heart disease. This type of diet works principally by reducing the most energy dense of the nutrients – fat. Fat per gram contains almost twice as much energy as carbohydrates or protein (9kcals vs 4kcals per gram respectively).
Currently low fat versions of foods are readily available in most supermarkets making the diet plans easy to obtain and start. The issue is that most people find this diet plan hard to stick to, which is potentially due to two reasons. Firstly as noted above carbohydrates principally do not have the same effect on satiety as fat and protein does making this type of diet harder to stick to due to hunger pangs. One solution is to ensure that the carbohydrate choice is high in fibre and protein is eaten along with the carbs. The diet becomes restrictive in that many foods that people enjoy contain reasonable amounts of fat which leaves lower fat foods typically tasting dry and bland. Add to this there is not an inbuilt regulator of calorie intake like many of the other diets and even with lower energy dense foods included in the diet it is still easy to overeat. Controlling portion sizes is required to make this diet work.
The last issue with this type of diet is the increasing amount of evidence that a balanced fat intake of roughly a third of your diet is required for optimal hormone production. This might not be an issue on a short term weight cut but long term wouldn’t be a prudent option.
IIFYM (If It Fits Your Macros) diet
A diet plan which does not restrict foods based on ‘‘dirty’ or ‘clean’ foods but rather creates a calorie intake and macronutrient target which can be obtained form eating a range of different foods. This diet is potentially the one hardest to define as it can cover more scope than the others which in principle is the diets aim.
With IIFYM (If It Fits Your Macros) you work out your desired energy intake from using a standard equation and tweak through trial and error to get the right energy intake. From here you can break that down into desired macronutrients using the kcals per gram mentioned before. As such someone will be left with a kcal intake and gram quantities of carbohydrate, fat and protein to hit each day as part of their diet. If you hit the macros worked out kcal intake takes care of itself so becomes redundant once macros are worked out.
Typically in most diets so far certain foods are seen as off limits but with IIFYM you can eat them as long as your daily total of each macronutrient is adhered to. This requires some work on the dieters part tracking what they eat and either a calorie counter/macronutrient book or an App like Myfitness Pal is typically used. The argument against this is certain foods are deemed bad and can impact the metabolism over the course of a diet, however seeing the large variance in dietary approaches so far its becoming clear that this might not hold up as well. This diet has the potential to be abused and long term can lead to sub optimal results and deficiencies if prudent choices are not made for the majority of the time.
Typically most people will tend to eat ‘cleaner’ foods when presented the choice for the most part as choosing foods which are energy dense due to being high in one particular macronutrient tends to make the rest of the days diet restrictive. Typically someone dieting will lean towards better choice foods to get their macronutrient quota but have the freedom to vary this and stay on track if social situations of cravings come into play by adjusting what they eat later to compensate and get their daily goals.
The 5/2 diet
A diet that involves eating normally for five days out of a seven-day period and greatly restricting the amount of food eaten on the other two days. This diet allows people to eat ‘normally’ for five days combined with restriction to around 500kcals on two days per week.
This is a small part of intermittent fasting type systems. The aim is that the reduction in kcal intake for two days will be enough to edge the person towards weight loss over the course of the week. Some suggestion periods of decreased kcal intake ca alter metabolism but there is scant evidence of this so far (especially only two days per week). What this might do is lead to some fat loss and a decrease in glycogen in the two days of fasting.
When someone goes back to eating ‘normally’ any energy taking in might be preferentially stored as glycogen rather than fat. The issue comes down to eating ‘normally’. Typically those in a position of needing to lose weight have not developed good dietary habits and overeating during this period might occur. In a best case scenario this would undo the efforts on the two days of fasting, in a worst case scenario it just reinforces bad dietary habits long term for the dieter.
So what can be learned?
As can be seen from the large variety of the diets above, all will cause weight loss if followed even if some do not seem as efficient or as effective as another. As such what should be the take home messages from the above?
Create a calorie deficit
Whether you choose a low fat diet or a low carb diet one thing is universally present in all these diets – calorie restriction and a negative calorie balance.
You cannot bend or break the laws of thermodynamics and a calorie deficit is required to see any substantial bodyweight/fat changes. As has been seen the process of creating a calorie deficit is the most important element as many of the diets above have polar theories but have all been used to assist in weight and fat reduction.
Focus on quality ingredients within the diet.
We don’t eat nutrients, we eat food that contains nutrients. Whenever you opt to restrict calories in order to lose weight you run the risk of some form of nutritional deficiency. As such choosing high quality nutrient dense foods for the same calorific value will reduce the risk of health issues long term from deficiency.
The same with any supplements you choose – pick high quality ones with no added fillers of fluff such as EQ Nutritions Diet Protein to supplement your diet plan.
Choose something which fits with your social framework and personal preferences
Nothing makes dieting harder than eating the opposite to friends and family constantly. Whilst there will always be a degree of having to forgo pleasures in life the less impact it has on your immediate society around you the easier it will be to stick to long term. Choose a diet which assists in building long term behavioural change in eating habits.
Speak to most people who diet and they say – ‘the diet worked but I have now put it all back on again’ (and sometimes with interest). From our perspective the diet didn’t work! Unless you are deliberately creating a short term situation such as being stage lean or making a weight class for a competitive event a diet should allow you to both lose weight and keep it off long term.
Often this means finding a system or diet which allows you to break the negative habits which made you gain weight in the first place even if you are not following the exact eating plan that got you back to your desired weight.
Whatever your choice adherence and sticking to a plan is a prerequisite. Choose wisely and stick to it.
1.Foster GD, et al. A randomized trial of a low-carbohydrate diet for obesity. New England Journal of Medicine, 2003.